What's the Idle Power Difference Between Hi/Low End CPUs?

I'm thinking about getting a small and thin device for mostly light weight work (note taking, presentation, etc.). Battery life is important for this one, so I'll get a low end CPU if that makes a big difference. Otherwise a faster CPU is still good to have.

Do I get any benefit if I sacrifice peak performance? If yes, how much?

I'm looking at both Intel and AMD chips.

 

With the tasks you described, a Pentium, i3, or A4 would be sufficient.

The battery life also depends on the laptop's design. I know back in 2008/2009, the Atom's northbridge chip consumed more power than the CPU.

 

Current platforms with a large battery have the best combination of the features most likely to be useable in 'any' situation. Simply say no to ULV chips - they are largely a waste of money (vs their performance) and do not give significantly more battery life in my experience.

A high end cpu (at least a dual core w/hyperthreading - a true quad core highly recommended) will idle at comparable levels to almost ULV cpu's if no load is present. An added benefit is that even when pushed to the redline - it will still drop to idle much faster than a lower end/entry level cpu and therefore get better overall battery life. Assuming of course that it is not kept at the max loads for very long.

I have a SNB and IB based setups (quad core) that offer almost 10 hours of light usage on battery power (and 17" screens at less than maximum settings, of course). With a high load and constant load (conversion of RAW images, for example) - those same systems will be done in less than an hour with a fully charged battery.

I would suggest to get the most current platform, as much RAM as you can install (16GB highly recommended for Win8x64 and SNB or IB platforms) and a power efficient SSD.

That will give you a system with all the attributes you asked for - but will also ensure you'll want to keep using this system even if your workload(s) change from day/month and/or year to year.

You didn't mention a price - but the above is achievable for around $1K (if you look/wait enough for a deal/sale).

Recap: Ideally; Win8x64 - 16GB RAM - an SSD - large capacity battery and a modern quad core (Intel) cpu.



With all this said - I would wait until Haswell is released in a few short weeks - it will give even better idle/low load performance at the same or better performance as SNB or IB platforms - and if you don't need/want it right away - the prices will be reasonable too for the new tech.

Hope this helped.

Good luck.

 

well, if I would share my opinion, Apple MacBook Air with SSD is simple and good choice depending the requirement you explain.
simple to use
long battery life
light weight, portable
but expensive

on other side I would suggest a windows 8 ultrabook with Intel ULV processor and SSD. in my experience Lenovo has some ultrabooks with good battery life.

if performance is not a big concern, main usage is for presentations etc. why not try a NETBOOK, 10"-12" ( with Intel Atom or Intel ULV processor ) are usually very good for battery life, SSD has a big role to play in battery life. I mean I had an ASUS EeePC 10" ( 250HDD, Intel Atom 1.6 CPU, 1G RAM) which use to give me 8-9 hours battery time. currently I have a netbook from Medion, almost same specs, it gives me about 6 hours with one battery charging. although mostly use it directly with AC adopter.

 

I've read that the new Intel Haswell chips are prioritizing low consumption. I would wait a month if you can then maybe pick up an i3 or i5 with the GT2 integrated graphics chip just in case you might want to run light 3d applications
An SSD is an essential battery saving choice as well.

 

An A4, A6 APU can also be an option, depending on how well the APU laptops perform.

 

No, not really a reason to consider AMD.

When it comes to hardware - the 'verdict' is 'guilty' until proven innocent - and AMD is far from Intel's performance/power envelopes atm (ie. 'guilty as charged' - send them back to lockup).

 

Hey, Richland has additional power saving features, so to completely ignore because of Trinity's performance is rather close-minded. I've also read lots of A4 users; for light tasks like browsing and movies, it's sufficient.

The main issue that the APUs have are the OEMs. Dell does not have a single laptop with an AMD APU. HP plans on watering down an APU laptop and reduce model choices. In comparison, there's hundreds of Intel laptops without a dedicated GPU.

To get an idea of how odd the OEMs' choices may be at times:

Amazon.com: ASUS A53SD-TS71 Core i7 4GB/750GB NVIDIA GT 610M Laptop: Computers & Accessories

i7-2670QM 2.2GHz
4GB DDR3
NVIDIA GeForce GT 610M 2GB Graphics

The HD4000 has a better performance than the GT 610m according to notebookcheck, nor would the 610m ever have enough performance to use the 2GB of VRAM, nevertheless 1GB. And that laptop used to be priced at $1,400 at launch.

And your equally ignorant users:

 

If idle power consumption is your primary concern and performance isn't important, then how about an Atom-based system?

Whereas there's little difference in idle power consumption between Core i3 vs i7 and even ULV vs quad core, there's a huge difference between Atom vs Core.

 

Atom also takes forever and a day (Until at least Silvermont) to complete any appreciable task, thus you'll probably end up with worse battery life since it spends more time at load.
Its a misconception, low end CPUs don't necessarily improve battery life. If anything, idle battery life might be worse as the low end chips are the worst binned from more powerful chips.
The ULV chips do have a slightly lower power draw at idle (we're talking maybe .5W-1W) as their idle voltage is slightly lower + 800mhz vs 1200mhz on the standard Ivy bridge chips. However, ULV chips are also slower under load so you have to be sure the machine isn't doing heavy continuous tasks as opposed to burst workloads. I would recommend the ULV chips if your machine is mostly for office and light multimedia duties where the workload is more burst whereas a general purpose machine would benefit more from the standard voltage chips.

 

I would advise caution with the ULV chips, particularly the so called "i7 ULV". They cost more than the standard chips, and the i7 ULVs are typically on par with the standard i3/i5, at much higher price.

How much are you willing to pay?

 

Your assumption is incorrect - there are tons of benchmarks out there showing that Clover Trail tablets get far better battery life than Ivy Bridge tablets do.

 

My point exactly as the OP seems to place a very high value on battery life but also somewhat cares about performance. Atom unfortunately, won't provide the performance. I personally wouldn't consider the i7 ULV unless the alternative was a non Silvermont Atom.

@peon
My mistake, after some reviews, it seems Atom wasn't quite as bad power wise as I first thought.
However, that power profile will cost dearly in performance which is about 3hrs difference when comparing the Surface Pro to the Acer Iconia. I wonder if the tradeoff is worth it as you will pretty much be unable to efficiently do infrequent but heavy tasks like transcoding or massive excel spreadsheets. Plus, the Atom GPU leaves much to be desired.

 

idleing/low power mode has negligible differences between all Intel's current CPU lineup. I can get almost 6 hours on my M17x R4 when I just want to run in power saving mode, and that is with a 3720qm chip.

 

The OP only stated that he or she intended to use the laptop for "light weight work" and then gave examples that perfectly fit that profile, so I'm guessing that the OP already has a desktop or a mainstream laptop and just wants something more portable. Given how the OP has never returned to this thread to provide further comments or clarification, your guess is as good as mine here.

 

Sorry for the delay. Thanks for the replies.

I already have a decent notebook for mobile performance needs. I'm looking for a more portable machine so I don't have to drag the big one every time or waste battery juice doing light weight work. Another reason to go shopping is I need a touch/stylus device for drawing stuff. I can go at least $2000+ if necessary.

Since hi/low end Core/APU chips offer similar idle power, I guess going high end would be a more reasonable choice. The more performance/feature I get from this portable device, the less likely I'll need the big one. Therefore I'm hesitant to go all-out about battery power and buy an Atom now. Besides, Atom devices appear to offer less battery capacity compared to i7/A10 ones, which offsets the low idle power benefit. Is there any surprising exception I'm not aware of?

I'm not in a hurry and will wait for Haswell. Not sure about Kaveri. ("Late 2013" means early 2014 for mobile, right?)

Not surprised at all. Many OEMs only mark their GPUs with VRAM size, so GT 610M 2GB is a great choice to cut down cost. I've seen too many Quadro Equivalents in the desktop workstation market to feel anything special about a 610M 2GB. There is still a difference though. The heaviest GPU workload for the workstations is usually Windows Aero (not talking about CG/CAD users) while the consumer ones do handle CoD or something.

 

Kaveri is expected to have GCN-based GPU and a Steamroller-based CPU (possibility triple modules, which will resemble more of a hexacore than a triple core).

If you can wait until 2013 Christmas shopping season, I'd suggest waiting, since Kaveri is a major upgrade over Richland/Trinity.

 

Touch/stylus device needed?

Sounds like a perfect match with a MS Surface Pro. And still well within your budget.

See:
Microsoft Surface Pro w/ 4GB, 128GB SSD, 10.6in Full HD, Stylus, Windows 8 Pro, Dark Titanium at Memory Express


Don't forget to add the Microsoft Type Cover to make this setup 'complete':

See:
Microsoft Type Cover for Microsoft Surface Tablets, Black at Memory Express

 

Surface Pro sounds like a good device, and I was kind of excited when it came out. Its specs is kind of awkward though. With an i5 Duo I should be able to do a bit non-light-weight work, but once I do 4GB RAM and 128GB SSD would run out in no time.

 

Who cares? Many have correctly pointed out the idle power between ULV/SV and even quads is likely the same. But they have gone beyond their expertise about ULV's. They just do not get it. But as they might of said who cares about idle power draw?

 

Probably very few. Look how many people want thin phone these days.